The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 13, 2019
Filed:
Oct. 20, 2017
Raydium Semiconductor Corporation, Hsinchu, TW;
Chih-Hsiung Chen, Zhubei, TW;
Yu-Chin Hsu, Hsinchu, TW;
Meng-Yi Chen, Kaohsiung, TW;
Chih Yuan, New Taipei, TW;
Raydium Semiconductor Corporation, Hsinchu County, TW;
Abstract
A mutual-capacitive touch sensing circuit includes an operational amplifier, an internal capacitor, a first switch˜a third switch. A first input terminal and a second input terminal of operational amplifier are coupled to a capacitor and ground respectively and an output terminal of operational amplifier outputs an output voltage. The internal capacitor is coupled to output terminal and first input terminal. The first switch is coupled to a first external charging voltage, capacitor and first input terminal. The second switch is coupled to a second external charging voltage and the capacitor. The third switch is coupled to a third external charging voltage, the second switch and capacitor. The second external charging voltage and third external charging voltage have same magnitude but opposite polarities. The first switch, second switch and third switch are switched in a specific order to selectively charge the capacitor with different external charging voltages.